* BaseBreakingCharacter: Chachi-nated, or De-Chachi-nated? Nick at Nite even made a marathon out of this premise, and viewers got to vote. This got even worse when Scott Baio became much more open about his extreme right-wing political stance in 2016, as one of the few Hollywood celebrities to openly endorse Donald Trump during his presidential campaign.* BrokenBase: Despite being the TropeNamer for JumpingTheShark, a term that was coined when Fonzie jumped over a shark during Season 5, opinions widely vary among fans on when the show actually started going downhill. Some argue that the show went downhill as early as Season 3, when the show started being taped in front of a live audience. Some will say when Fonzie actually jumped the shark. Others will say when Richie and Ralph left the show after Season 7. A number of fans will even argue that the show stayed good for all 11 seasons.* DarkerAndEdgier: By the final season. Well, as D&E as you could be with this show. More dramatic moments (among them an AttemptedRape of Joanie), the use of "hell" and "damn", and Fonzie showing more weakness.* EarWorm: ** C'mon, sing it with me: "[[TitleThemeTune Sunday, Monday, Happy Days...]]".** The "Pumps Your Blood" song.* EnsembleDarkhorse: ** Fonzie in the first two seasons, so much that he became a BreakoutCharacter and was promoted to second billing, after Ron Howard.** Mork was only supposed to be a one-shot character and his episode AllJustADream, but Creator/RobinWilliams' performance was such a hit that the episode was revised to make the events real after all and gave him his own spinoff.* FranchiseOriginalSin: The moment of [[JumpingTheShark vertical ascension over an aquatic carnivorous animal]] is considered merely the point where Fonzie's {{Flanderization}} into a superhuman and the loss of the 1950s motif reached its zenith. Both those things had subtly been going on as the seasonal rot kicked in.* HarsherInHindsight: Joannie and Chachi's romance was irrevocably ruined after Scott Baio's insensitive statement that Erin Moran deserved her early death because of her drug addictions.* HilariousInHindsight: In one episode, a martial arts class is taught by Arnold, played by Pat Morita. Happily, [[Film/TheKarateKid Daniel-San]] was a better student than [[ButtMonkey Richie]].* MemeticBadass: Fonzie is treated this way even InUniverse. Sometimes he's able to come out on top by just ''appearing'' in one scene.* ReplacementScrappy: Roger, the nephew introduced after the departure of the main hero Richie Cunningham. Unlike adorkable everyman Richie, Roger is seen by most fans as a forgettable FlatCharacter. * TheScrappy:** Roger, and really anyone introduced in season 8 and beyond.** Chachi was ''always'' [[TheScrappy The Chachi]]. He was popular with the girls, but retroactively, amongst older fans? Please.* SeasonalRot: It started out as a very cool, low-key show, then became the ideal version of a standard sitcom with a StudioAudience. It started getting worse (the Trope-Named Shark-Jump) even before Richie left, but only got worse after that. Fonzie got a temporary full-time girlfriend for one season, and things got increasingly worse with gimmicks and nonsense until a thankfully fantastic final episode.* SomeAnvilsNeedToBeDropped: According to Garry Marshall, "Richie Almost Dies" was written for this reason. He explained that he was contacted by counselors working with abused children who watched the show. These kids refused to cry and kept their emotions under wraps, so Marshall wanted to have [[HeroicBSOD Fonzie go through an emotional breakdown]] in order to [[AnAesop show these kids that it was okay to cry]].* {{Squick}}: In "The Cunningham Caper", Joanie talking about barf bags. Also, all the bad meat in the liver episode. Squicked out Fonzie too.----